RESUMEN
Mitogen-activated protein kinase (MAPK) cascades are frequently used signal transduction mechanisms in eukaryotes. Of the five MAPK cascades in Saccharomyces cerevisiae, the high-osmolarity glycerol response (HOG) pathway functions to sense and respond to hypertonic stress. We utilized a partial loss-of-function mutant in the HOG pathway, pbs2-3, in a high-copy suppressor screen to identify proteins that modulate growth on high-osmolarity media. Three high-copy suppressors of pbs2-3 osmosensitivity were identified: MSG5, CAK1, and TRX1. Msg5p is a dual-specificity phosphatase that was previously demonstrated to dephosphorylate MAPKs in yeast. Deletions of the putative MAPK targets of Msg5p revealed that kss1delta could suppress the osmosensitivity of pbs2-3. Kss1p is phosphorylated in response to hyperosmotic shock in a pbs2-3 strain, but not in a wild-type strain nor in a pbs2-3 strain overexpressing MSG5. Both TEC1 and FRE::lacZ expressions are activated in strains lacking a functional HOG pathway during osmotic stress in a filamentation/invasion-pathway-dependent manner. Additionally, the cellular projections formed by a pbs2-3 mutant on high osmolarity are absent in strains lacking KSS1 or STE7. These data suggest that the loss of filamentation/invasion pathway repression contributes to the HOG mutant phenotype.
Asunto(s)
Glucógeno/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/fisiología , Clonación Molecular , Genotipo , Glicerol/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Concentración Osmolar , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Transducción de Señal , Sorbitol/farmacología , Supresión Genética/efectos de los fármacos , Transcripción GenéticaRESUMEN
Delivery of quality patient care and management of patient outcomes is critical to the success of academic medical centers in the ever-changing health care market. The University of Iowa Hospitals and Clinics (UIHC) promotes quality care through the provision of organizational structures and processes that are described in this article. In addition, quality of care and outcomes management are described by members in various roles within the UIHC health care system. It is the authors' belief that understanding quality from these various perspectives helps UIHC work across departments to achieve excellence in patient care.